1. Field of the Invention
The present invention relates generally to a magnesium-boron composite, and more particularly, to making magnesium-boron composites by mechanically mixing magnesium powders with boron powders. A small amount of lithium may be added for ductility.
2. Description of the Prior Art
The ratio of elastic modulus E over the density p, known as specific stiffness E/p, hereinafter referred to as E/p, is a very important design criterion for many structural components such as I-beams, and the like. Materials with high E/p values are especially useful in aero-space applications where stiff materials with low densities are needed.
Most structural materials, for example, steel, aluminum, nickel, titanium, magnesium and their alloys, have roughly the same E/p values of about 100 .times. 10.sup.6 in. It should be noted that among these materials the density tends to increase as the elastic modulus E increases, yielding approximately constant E/p values. For example, although the elastic modulus E of steel is 4.8 times that of Magnesium (Mg), the density of steel is about 4.5 times that of Magnesium (Mg). There are relatively few ways of increasing the elastic stiffness for a material. Since modulus varies with orientation in a single crystal, one method is to produce a specific orientation for most of the grains in a polycrystalline material. This will yield an anisotropic material, that is, E will be high in some direction but low in other directions. Such a material may be undesirable in some design applications.